Not Applicable
1. Field of the Invention
The invention relates generally to an improved motion detector and alarm system for actuating an alarm device in response to movement of an object, and more particularly to a portable motion detector and alarm system which is easy to install and operate and is capable of detecting motion relative to a variety of predetermined positions.
2. Prior Art
The problem of protecting homes, businesses and other premises against unauthorized intrusions is becoming increasingly important due to the increase in vandalism, theft and even physical attacks upon the inhabitants. Various prior art systems have been developed to address the problem and numerous examples exist of alarm or warning devices. One commonly used protective system involves wiring doors and windows in such a manner that an unauthorized opening of the door or window activates an electric circuit which in turn produces an alarm.
For example, U.S. Pat. No. 4,271,405 to Kitterman discloses an alarm control system for protecting a premises including a four conductor bus line leading from a master control station and extending about the interior perimeter of the premises. Sensors positioned near each port of entry to be monitored are connected in parallel relationship to the bus line. Each sensor carries a biased reel carrying line secured to a window, door, screen or the like. Disturbance of a sensor causes a magnetically responsive switch therein to generate a pulse triggering circuitry within the control station to activate the desired alarm device.
While effective, this system requires extensive wiring of the premises as a bus line must be routed about the interior perimeter of the premises between a master control station and the ports of entry at which the motion sensors are to be located. Hence, this system is time consuming and complicated to install, and installation may require expertise beyond that of the average home or business owner. Once installed, the sensors of this system are not easily relocated. Further, the system may be defeated by cutting the wires extending between the sensors and the master control station.
U.S. Pat. No. 3,781,836 to Kruper et al discloses an alarm system including a magnetic pulse generator for producing an output pulse in response to a change in magnetic flux in response to an intrusion of a designated area. A radio transmitter circuit responds to the pulse from the magnetic pulse generator by transmitting a signal to a remote receiver circuit which in turn generates a pulse for actuating an intrusion alarm circuit. The system requires a complex linkage assembly to translate motion of the object to motion of a magnet. In addition a relatively bulky pick-up coil assembly is necessary to generate the pulse to be applied to the transmitter circuit.
U.S. Pat. No. 3,696,380 to Murphy discloses a portable alarm device with a battery or low voltage operated sound signal triggered by a magnetic reed switch which is closed to complete the circuit by a magnet attached to a movably mounted arm, the poles of the magnet being positioned perpendicular to the longitudinal dimension of the contact strips of the reed switch to cause the reed switch to close when the magnet is in either of two positions relative to the switch.
A need remains for a motion detection and signal generating system which is small in size, easily transport-able, easy to install and which can sense motion relative to any desired initial position of an object. An additional desirable capability of the foregoing system would be to provide information about the detected motion to a remote location, such as a law enforcement or other security agency.
Accordingly, it is a principal object of the invention to provide a system for detecting the movement of an object comprising: an object whose movement is to be detected, movable magnet means coupled to the object such that movement of the object results in movement of said movable magnet means, and means for detecting movement of the movable magnet means and providing an indication of the movement. The means for detecting is in communication with the movable magnet means.
The system further includes radiating means for wirelessly transmitting a predetermined signal in response to the indication of movement, the radiating means being coupled to the means for detecting. The object whose movement is to be detected may be coupled to the movable magnet means by a wire means which can also serve as the radiating means.
The system further includes means for receiving the predetermined signal, the means for receiving being separate from and located at a distance from the radiating means. The system preferably includes means for generating an alarm signal when the predetermined signal is received by the means for receiving. The alarm signal thus generated may be audible, visual or electronic and may include speakers, warning horns, lamps and the like.
It is a further object of the invention to provide a method of detecting movement of one or more objects comprising the steps of: a) coupling each object whose movement is to be detected to a corresponding movable magnet such that movement of any object results in movement of the corresponding magnet; b) detecting the motion of the corresponding magnet; c) transmitting a predetermined signal in response to the detected motion, and, d) receiving the predetermined signal at a distance from the object, or objects, whose motion is to be detected.
The method may include the further step of providing an alarm signal when the predetermined signal is received by the receiver means. The alarm signal may be audible, visible, or may be an electronic alarm signal which is transmitted to a remote alarm center via a telecommunications means such as a telephone line.
It is a further object of the invention to provide a movement detection and alarm system which may be affixed to a wide variety of objects including inside doors, outside gates, garage doors, children""s barriers such as xe2x80x9cbaby gatesxe2x80x9d, valuable wall hangings and paintings, and countless other objects.
It is a further object of the invention to provide a movement detection and alarm system which is portable and is easily packed in a suitcase and transported with a traveler to be later installed on motel or hotel room doors and windows whenever additional protection is desired by the traveler.
It is a further object of the invention to provide movement information to a remote location, such as a law enforcement or security agency.
The present invention relates to a portable security alarm system which can be installed on a temporary basis and removed from an object whose movement is to be detected comprising a motion detecting and radio signal transmitting member, means for selectively coupling and decoupling said motion detecting and radio signal transmitting member relative to said object whose movement is to be detected, and a combined radio signal receiving and alarm generating member for receiving a signal from said combined motion detecting and radio signal transmitting member and producing an alarm. The alarm system also preferably includes a remote control member for selectively actuating and deactuating said combined radio signal receiving and alarm generating member. The alarm system also preferably includes an information gathering device for gathering movement information and a remote notification device for providing the movement information to a remote location.